PRODUCTS, ADVENTITIOUS. 



13.1 



many surgical writers confounded, under the 

 erroneous name of *' cartilaginous exostosis " 

 (erroneous, if for no other reason, because 

 the formation in question may spring from 

 other tissues than bone), with products of 

 essentially different character, and by some 

 other authors described as colloid cancer. 



When uncu^ enchondroma exhibits itself 

 as a tumour of moderate size and spheroidal 

 non-lobulated shape, encased in cellular mem- 

 brane, or (if it spring from bone) in perios- 

 teum, ossified or not. The section discovers a 

 firmly gelatinous substance, rather pellucid, of 

 very pale greyish or greenish yellow tint, set 

 (without firm adhesion) in loculi inclined to 

 spheroidal outline, varying in size, and having 

 their walls formed of a dense dull white 

 tissue (Jig. 95). One of the rough marks 



Fig. 95. 



Section of Enchondroma. (After Mutter.) 



of distinction between this growth and colloid 

 cancer consists in the mode of arrangement 

 of the walls of the loculi : in the latter, when 

 fully grown, the walls seem cut across sharply 

 at right angles with their course ; in the for- 

 mer it is extremely common to find the walls 

 exhibiting flat ami extensive surfaces to the 

 eye, as though the loculi had been opened to 

 a very small extent only. 



The general mass is firm 3 when the invest- 

 ment is periosteal or bony, proportionally 

 increased. The intra-locular matter is in it- 

 self soft, yet has a sharp fracture. Bony 

 matter in its interior of course increases its 

 consistence, and may be formed of: 1, the 

 walls of the loculi converted into thin osseous 

 plates, which give a crackling cri.s^ness to the 

 mass; 2, particles of the spongy tissue of the 

 original bone in which it has grown ; 3, sta- 

 lactiform osteophjtes springing into its sub- 

 stance. 



No appearance of vessels strikes the un- 

 assisted eye in these masses ; but von VVal- 

 ther and Weber (Grafe and Walther's Journ., 

 b. xxiii. s. 351.) are said by Miiller to have 

 injected the walls of the loculi. 



Microscopically examined, the fibrous por- 

 tion of the growth is found to be composed 

 of transparent interwoven fibres. The jelly- 

 like part consists of cells several times larger 

 than the red blood-corpuscle, generally speak- 

 ing, containing only nuclei in their interior, 

 hut in some instances two or three sub-cells, 

 each provided with its own nucleus. The 



nuclei, flattened, oval or circular, vary in 

 diameter. The cells (except in excessively 

 rare cases) are in close contact with each 

 other, and no inter-cell substance discern- 

 ible between them : the cartilaginous ma- 

 terial does not advance beyond the embryonic 

 stage. Such is Miiller's description ; but it 

 is certain that tumours having the characters 

 of enchondroma perfectly developed to the 

 naked eye, and yielding gelatin, may be 

 wholly deficient in cartilage corpuscles, and 

 contain simple granulated cells in a fibrous 

 stroma. 



Spiculated bone corpuscles are sometimes 

 scattered through the tumour. 



From this account it would appear, that 

 although the endogenous mode of growth of 

 the cells occurs occasionally in this forma- 

 tion, it is neither uniform nor constant ; their 

 development proceeds more frequently from 

 blastema lying outside such cells as are already 

 evolved. The endogenous development was 

 observed especially by Miiller in an enchon- 

 droma of the parotid gland. Whether the 

 inter-cell substance is generated by thickening 

 of the walls of the cells, or by the hardening 

 of a blastema unconnected, except in respect 

 of proximity, with these, is matter of dispute. 

 Enchondroma is essentially composed either 

 of chondrin or of glutin ; of the former in 

 by far the greater number of cases ; of the 

 latter, in Miiller's specimen connected with 

 the parotid gland, and in another connected 

 with the ileum, recently added to the Uni- 

 versity College Collection. 



The bones are the favourite seat of this 

 growth. Miiller has collected thirty-six cases, 

 in thirty-two of which those organs were af- 

 fected : the metacarpus and phalanges 25 times; 

 the tibia 3 ; the ileum 1 ; the cranium 1 ; the 

 ribs 1, Of the four remaining tumours, 1 ex- 

 isted in the parotid ; 1 in the mamma of a 

 dog; 2 in the testicle. In its favourite seat 

 *- the metacarpus and phalanges this dis- 

 ease produces singular distortion and irregular 

 tuberot&tfess of the hand (Jig. 96). 



Fig. 96. 



Enchondroma, from model in Univ. Coll. Mus. 



Enchondroma, springing from bone, is in- 

 vested or not with a bony capsule. When it 

 grows in the interior of a long bone, expan- 

 sion, and not perforation of the shell, occurs; 

 the cancellated structure first, and then the 



K 3 



